DNA sequences which lead to the formation of polyfructans (levans), plasmids containing these sequences as well as a process for preparing transgenic plants

Abstract

DNA which leads to the formation of polyfructans (levans), plasmids containing this DNA, as well as processes using plasmids for preparing transgenic plants with polyfructan (levan) expression.

What is claimed is:  
     
       1. A method for producing a transgenic plant with modified polyfructan formation comprising: 
       transforming a plant cell so as to contain and express a DNA molecule encoding a bacterial polyctan sucrase wherein polyfructan sacrase expression leads to polyfructan sucrase activity in the vacuoles of the plant; and  
       regenerating an intact whole plant from the cell which contains and expresses the DANA molecule.  
     
     
       2. The method of  claim 1  wherein the DNA molecule is derived from  Bacillus amyloliquefaciens  or  Streptococcus mutans.    
     
     
       3. The method of  claim 2  wherein the DNA molecule is derived from  Bacillus amyloliquefaciens.    
     
     
       4. The method of  claim 2  wherein the DNA molecule is derived from  Streptococcus mutans.    
     
     
       5. A method for producing a transgenic plant with modified polyfructan formation comprising: 
       transforming a plant cell so as to contain and express a DNA molecule encoding a polyfructan sucrase wherein polyfructan sucrase expression leads to polyfructan sucrase activity in the vacuoles of the plant and wherein the DNA molecule is derived from  Bacillus amyloliquefaciens; and    
       regenerating an intact whole plant from the cell which contains and expresses the DNA molecule.  
     
     
       6. A method for producing a trasgenic plant with modified polyfructan formation comprising: 
       transforming a plant cell so as to contain and express a DNA molecule encoding a polyfructan sucrase wherein polyfructan sucrase expression leads to polyfructan sucrase activity in the vacuoles of the plant and wherein the DNA molecule is derived from  Streptococcus mutants ; and  
       regenerating an intact whole plant from the cell which contains and expresses the DNA molecule.  
     
     
       7. A plant obtainable from the method of any one of  claim 1 ,  5 , or  6 . 
     
     
       8. An intact whole transgenic plant comprising a DNA molecule encoding a bacterial polyfructan sucrase wherein the transgenic plant expresses the DNA molecule and has polyfructan sucrase expression wherein the polyfructan sucrase expression leads to polyfuctan sucrase activity in the vacuoles of the plant and has an altered amount of polyfructan sucrase activity relative to a non-transformed plant. 
     
     
       9. The plan of  claim 8  wherein the DNA molecule is derive from  Bacillus amyloliquefaciens.    
     
     
       10. The plant of  claim 8  wherein the DNA molecule is derived from  Streptococcus mutans.